(P177) CANNULATION STRATEGY IMPACTS PERIOPERATIVE SAFETY IN ACUTE TYPE A DISSECTION: CANADIAN MULTICENTRE DATA

Background: Cannulation strategies in ATAD remain variable and consensus regarding the optimal strategy is lacking. We therefore compared perioperative outcomes of four common cannulation strategies in acute type A aortic dissection (ATAD) repair from a large multicentre national cohort.

METHODS AND RESULTS: Patients undergoing ATAD repair with circulatory arrest (2002-2021) were included from a national aortic database of 9 cardiac surgical centres. Cannulation strategies included: Direct Aortic, Axillary, Innominate, Femoral, and Multiple (defined as any combination of the previous four strategies). Type B and chronic presentations were excluded. Primary outcomes included in-hospital death, stroke, and perioperative complications. Multivariable logistic regression was performed for the primary outcomes to adjust for baseline and intraoperative differences, year of operation, and centre. 941 patients (mean age 60.4±12 years, female 30%) underwent ATAD repair with the following cannulation strategies: Axillary (N=442, 49%), Femoral (N=213, 23%), Multiple (N=145, 15%), Aortic (N=88, 9%), Innominate (N=53, 6%). Femoral patients were slightly younger than Aortic (61±14 vs 66±13, p=0.012). Malperfusion presentation occurred in 35% (N=330) and was significantly more common among Femoral patients (48% N=102), [Aortic: (N=12, 24%), Axillary: (N=152, 34%), Innominate: (N=10, 19%), Multiple: (N=45, 31%), p< 0.001]. Aortic valvular pathology, presentation with rupture, and highest preoperative lactate were similar between groups. Cardiopulmonary bypass times were significantly shorter among Innominate patients: 162±63min [Axillary (219±87min), Femoral (217±76min) patients, Multiple: 212±91min, Aortic: 190±80min, p < 0.001]. Duration of circulatory arrest varied by cannulation strategy [Axillary: 33±22, Femoral: 32±20, Multiple: 32±22 Aortic: 26±17, Innominate: 26±18, ANOVA p=0.03 post-hoc p=NS]. Antegrade Cerebral Perfusion was significantly more common among Axillary (N=412, 93%), Multiple (N=115, 79%), and Innominate (N=52, 98%) patients, compared to [Femoral: (N=86, 40%), Aortic: (N=40, 46%), p< 0.001]. Unadjusted postoperative outcomes identified that rates of death, stroke, ICU length of stay, hospital length of stay, and prolonged ventilation were significantly worse among Femoral patients (Table 1). After adjustment for baseline and intraoperative differences, Axillary cannulation was independently protective against death and stroke [death OR: 0.59 (95%CI 0.40, 0.87) p= 0.02; stroke OR 0.58 (95%CI 0.40, 0.83) p = 0.01, relative to Femoral], Figure 1.

Conclusion: According to Canadian multicentre data over two decades, cannulation strategy is an independent predictor of hospital outcomes for patients undergoing ATAD repair. Axillary cannulation may reduce risk of death and stroke in ATAD patients. Further study is needed to quantify benefit of innominate cannulation. Malperfusion is an independent predictor of death and stroke.